Function core::core_simd::swizzle_dyn::transize

unsafe fn transize<T, const N: usize>(
    f: unsafe fn(_: T, _: T) -> T,
    bytes: Simd<u8, N>,
    idxs: Simd<u8, N>
) -> Simd<u8, N>where
    LaneCount<N>: SupportedLaneCount,

🔬This is a nightly-only experimental API. (portable_simd #86656)

This sets up a call to an architecture-specific function, and in doing so it persuades rustc that everything is the correct size. Which it is. This would not be needed if one could convince Rust that, by matching on N, N is that value, and thus it would be valid to substitute e.g. 16.

Safety

The correctness of this function hinges on the sizes agreeing in actuality.